1. Field of the Invention
The present invention relates to a connector with a double locking mechanism for accommodating terminals therein and, more particularly, to a connector having a flexible engaging lance provided in the terminal housings of the terminal housing thereof and a terminal retainer each for holding the terminals.
2. Description of the Prior Art
In conventional connectors, a lance integrally molded with the connector housing is used to lock a terminal crimped to an electrical wire (hereinafter referred to as "terminal") in the terminal housings of the connector housing. The lances are usually not strong enough to hold the terminals securedly, causing the terminals to be incompletely inserted and seated in the connector housing. To avoid such problems, a connector with a double locking mechanism, for an example, Japanese Laid-open Patent Publication No. 64-54678 published Mar. 2, 1985 is proposed. The double locking mechanism consists of a connector housing and a retainer provided independent to the connector housing. In this connector, the retainer is used to secure the terminals in the terminal housings and to prevent an accidental disconnection of the seated terminals. One such connector is shown in FIG. 13.
In this connector with a double locking mechanism, a through-hole 3 is typically provided in the middle of the connector housing 1 so that a retainer 2 can be inserted down into the through-hole 3, as shown in FIG. 13, to secure the terminals.
With this connector, terminals (not shown) crimped to the ends of the electrical wires are inserted to terminal housings 4 formed in the connector housing 1. A lance (not shown) is molded in each of the terminal housings 4 to lock the terminal in the terminal housing 4. The retainer 2 is then inserted in the through-hole 3, and locking tabs 5 formed on the retainer 2 also lock the terminals. The terminals are thus secured by two independent means and are reliably prevented from accidental extraction.
The problem with this connector is its manufacturability. Specifically, the terminal housings 4 are open to both the front and back sides of the connector housing 1. And, the through-hole 3 is opened to both the top and bottom sides of the connector housing 1. Therefore, a pair of dies for molding the front and back sides of the connector housing 1, and a slide die which slides perpendicularly to the front/back dies are required to mold the connector housing 1.
When the slide die is used, the construction of the mold becomes more complex and thus expensive, and molding also takes longer time.